This game is much more difficult than Arkham Asylum. I recent completed AA on hard and did most of the challenge rooms, getting most of the challenge room medals and more, so I can directly compare AC to AA since AA is fresh on my mind. AA usually had gargoyles nearby if you needed a place to escape, not so much in AC. In AC, you may not have a place to escape to, and even if you do, the enemies have wizened up and will simply throw a grenade after you if you stay in one place.
You need to plan escape routes, escape plans, a opening, a plan to separate armed hostiles and more. Fucking fantastic gameplay.